light brahma rooster?

I have a light brahma that is 4 1/2 months old who is still not fully feathered and acts very aggressive with other chickens. Hangs out by herself, gets to treats first, very aggressive w/ my younger chickens--herds them into one corner of coop, keeps them in the roost, etc. I will try to post pics later when I find my camera, but does this sound like a rooster? I guess it does, but could it possibly be a hen??

okay, so i found my camera, and was searching everywhere for the Brahma. She had been wanting to get in the roost about an hour ago but my kids had knocked down the the ladder. We put it back up and when I was searching for my camera, I realized she was still in there. So my 3 1/2 year old climbed into the roost and shouted, "she's laying an egg!" so I guess my question is answered!